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NEO Asteroid 1998 OR2,
Wolf 359 Parallax Program

Posted: 24 April 2020

Open: Thursday, 23 April 2020, 1819 MST
Temperature: 91°F
Session: 1460
Conditions: Mostly clear, breezy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
1.25" 15mm eyepiece
Focal Reducer

iPhone 11 Pro Max

1827 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed the planet Venus, 102X and 163X + Variable Polarizing Filter (VPF). The view at 163X dimmed by the filter was very good.

Mounted the iPhone 11 Pro Max on the 15mm eyepiece using the Levenhuk adapter. I did some iOS app tests for an upcoming review.

I then used the iOS app NightCap Camera for this afocal 163X+VPF image of Venus (ISO 500, 1/50sec, 1X lens).


1851 MST: the high thin clouds were increasing in sky coverage.

1902 MST: sunset. Calm now.

Slewed to the star Regulus and SYNCed the AutoStar in preparation of imaging Near Earth Object Asteroid (52768) 1998 OR2, clouds permitting. The asteroid will have its closest approach to the Earth on 29 April 2020, passing about 4 million miles from the Earth.

1924 MST: the clouds were moving eastward away from the location of the asteroid.

1927 MST: dome OFF.

Mounted the D850 DSLR at prime focus + focal reducer.

2007 MST: focused on the star Regulus using the Meade Bahtinov Mask and locked the 12" primary mirror using the ScopeStuff LX600 Mirror Lock. Then began waiting for the end of Astronomical Twilight (2028 MST).

2020 MST: Meade Stella Wi-Fi ON.

Used SkySafari 6 Pro on the iPhone to GOTO Asteroid 1998 OR2.

2022 MST: StarLock ON.

2028 MST: began doing StarLock autoguided images of Asteroid 1998 OR2. A 1 minute exposure at ISO 6400, White Balance 5560K, was done every two minutes. This is a stack of all five images showing the rapid motion of the asteroid.


The asteroid was moving so fast that its image trailed during the 1 minute exposures.

I merged (and cropped) the 5 images to show the asteroid moving against the background stars. A faint satellite appears near the asteroid's image in the last frame.


Next, the 12" telescope was slewed to the nearby star Wolf 359 using SkySafari 6 Pro. The New Horizons spacecraft would be imaging Wolf 359 at 2100 MST this night for The New Horizons Parallax Program.

2042 MST: Wi-Fi OFF.

2100 MST: I began imaging Wolf 359 at prime focus + focal reducer. Unfortunately, seeing conditions began deteriorating just as I started imaging, resulting in erratic autoguiding by the StarLock. 2106 MST: finally managed to get a good image (40 seconds, ISO 6400, WB 5560K) of Wolf 359. This cropped image shows the star.


It will be interesting to compare my image (from the Earth) to the image captured by the New Horizons spacecraft (5 billion miles from the Earth).

2111 MST: StarLock OFF.

2117 MST: LX600 OFF.

2124 MST: dome ON.

2130 MST: took a Sky Quality reading and reported the results to the Globe at Night. The neighbor's bright, unshielded, floodlights were coming on very rapidly (packrats setting off the motion detector?) and were ON when I took my sky reading. This nuisance light that trespasses onto our property was mentioned in my report to Globe at Night.

Close: Thursday, 23 April 2020, 2135 MST
Temperature: 66°F
Session Length: 3h 16m
Conditions: Clear, SQM 21.16

I have posted my review of the ScopeStuff Camera Mount.

My 3rd interview in support of International Dark Sky Week has been posted. Or at least, some of my comments. Click to read the Clearer Skies Bring Opportunities For Stargazing article.

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